Multiple link tire belt

ABSTRACT

The present invention is an improved tire design including a continuous annular band or a belt formed of a plurality of relatively flat rigid plates embedded in the rubber between the tread and body plies. The plates are curved to conform to the radius of the tire and are pivotally linked or otherwise pivotally connected together thereby creating a flexible annular belt that is extremely stiff in the in-plane or steering torsional direction due to the engagement of the side edges of the adjacent plates when experiencing an in-plane or steering torsional force but flexible in the radial direction due to the pivotal connection between the adjacent plates.

CROSS REFERENCE TO RELATED APPLICATION

This application is a Divisional Application of currently U.S. patentapplication Ser. No. 08/732,826, filed on Oct. 15, 1996, now U.S. Pat.No. 5,817,197 the disclosures of which are incorporated herein byreference.

BACKGROUND OF THE INVENTION

1. Technical Field

The present invention is generally directed to tires including passengertires, light truck tires, truck and bus tires, racing tires, andtemporary spare tires, and more particularly to an improved tire ofmultiple plate construction. Specifically, the present invention is animproved tire manufactured using a multiple link tire belt design madeof flat plate or plates curved to conform to the radius of the desiredtire where the plates are linked or otherwise connected together therebycreating a flexible ring that is extremely stiff in the in-planetorsional direction but flexible in the radial direction.

2. Background Information

With the advent and rapid expansion of automobiles and other vehicles inthe late nineteenth and all of the twentieth century, the use andimportance of tires as the means of contact between the automobile andthe road has grown. This is particularly true as the speeds at whichvehicles are operated has risen and continues to rise. In addition,today's varying road designs and conditions make the tire and itsconstruction, expected life span, and properties of critical importance.

Numerous tire designs both patented and not patented are well known inthe art and have been for almost one hundred years. Generally, tiresinclude various chemicals compounded into the natural or syntheticrubber resulting in a continuous rubber compound that encircles a rim ofa wheel where the rubber compound is able to withstand heightened wearand heat as well as aging. Fabric such as rayon, nylon, or polyester arealso often used to give the tire body added strength and resilience.This fabric when layered under the tread rubber will also increasemileage and improve handling. A steel wire is used in the bead area tohold the tire to the rim.

Generally, the rubber compound making up the tire has two parts, namelythe tread section and the body section. The tread section is the outerface which contacts with the road and therefor should preferably providethe highest levels of traction possible while also resisting wear andabrasion from the road contact. The body section fills out the remainderof the tire and is required to provide the necessary tire strength andflexibility.

Three overall types of tires are principally known, namely the bias typetire, the belted bias type tire, and the radial tire. All three typesuse successive plies consisting of cords of steel wires applied along aspecific configuration.

Specifically, bias tires have typically two or more plies of cords.These plies of cord extend diagonally across the tire from bead to bead.The cords run diagonally in opposite directions in each successive ply.A treaded rubber outer covering envelopes the plies.

Belted bias tires use the same ply technology as biased tires exceptbelts of material are inserted in between the layers. Specifically, thebelts of material are circumferentially aligned around the tire inbetween the plies and the treaded rubber outer covering.

Radial tires differ significantly from the bias tires because the cordsdo not extend diagonally and instead extend transversely from bead tobead. This transverse extension of the cords in each ply is such thatthe cords are substantially perpendicular to the direction of travel.Belts of material are then placed circumferentially around the tire.

Overall, the today's tire designs typically involve tires made of twoply belts where each belt is made of steel wires. It is well known thatan additional ply may be added to provide better cornering. Onealternative design also known in the art involves usingcircumferentially continuous banded belts to define the tire.

Other tire designs include plates added into the rubber compound toprotect the tire against puncture. It has also been found that theseplates minimize friction between different plies and thus reduce heat inthe tire.

Some examples of prior art tires containing internal reinforcementsextending in an annular fashion circumferentially around the tirebeneath the tread area are shown in U.S. Pat. Nos. 500,468; 559,987;560,196; 939,611; 1,481,488; 1,482,217; 2,160,219; 3,640,329 and4,456,048.

However, all of these known designs lack the combination of sufficientstiffness in the in-plane torsional direction as needed for enhancedcornering coupled with sufficient softness for radial and out of planebending deformations as needed for a good ride.

SUMMARY OF THE INVENTION

Accordingly, it is an object of the present invention to provide a tirethat provides enhanced cornering properties.

It is a related object of the present invention provide a tire having atleast one belt that is extremely stiff in the in-plane or steeringtorsional direction but quite flexible in the radial direction.

It is a further object of the invention to provide a tire that providesa good ride since it is soft when experiencing radial and out of planedeformations.

It is a related object of the present invention to provide a tire havingat least one belt formed of a plurality of rigid links hingedlyconnected together for flexibility in the radial direction but in whichthe adjacent edges come into contact and create a nearly rigid structurewhen experiencing the in-plane forces.

Still other advantages and benefits of the invention will becomeapparent to those skilled in the art upon a reading and understanding ofthe following summary and detailed description.

These objective and advantages are obtained by the pneumatic tire of thepresent invention the general nature which may be stated as including atire that is extremely stiff in the in-plane torsional direction andflexible in the radial direction wherein said tire comprises an annularcarcass having at least one ply, the ply comprising a plurality ofelongated strands, a flexible annular belt comprised of a plurality ofrigid plates, each plate separated from and pivotally connected to anadjacent plate by a pivot means, and a rubber compound enveloping thecarcass and flexible belt.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred embodiments of the invention, illustrative of the best modesin which the applicant has contemplated applying the principles, are setforth in the following description and are shown in the drawings and areparticularly and distinctly pointed out and set forth in the appendedclaims.

FIG. 1 is a perspective view with portions broken away and in sectionshowing the tire link belt of the present invention;

FIG. 2 is a cross sectional view of the tire shown in FIG. 1;

FIG. 3 is an enlarged fragmentary perspective view of a first embodimentof the link belt of the present invention;

FIG. 3A is a further enlarged fragmentary sectional view taken alongline 3A--3A in FIG. 3;

FIG. 4 is an enlarged fragmentary perspective view of a secondembodiment of the link belt of the present invention;

FIG. 4A is a further enlarged fragmentary sectional view taken alongline 4A--4A in FIG. 4;

FIG. 5 is an enlarged fragmentary perspective view of a third embodimentof the link belt of the present invention;

FIG. 5A is a further enlarged sectional view taken along line 5A--5A inFIG. 5;

FIG. 6 is an enlarged fragmentary perspective view of a fourthembodiment of the link belt of the present invention;

FIG. 6A is a further enlarged sectional view taken on line 6A--6A ofFIG. 6;

FIG. 7 is an enlarged fragmentary perspective view of a fifth embodimentof the link belt of the present invention; and,

FIG. 7A is a further enlarged sectional view taken on line 7A--7A ofFIG. 7.

Similar numerals refer to similar parts and elements throughout thedrawings.

DESCRIPTION OF THE PREFERRED EMBODIMENT

The present invention is shown generally in FIG. 1 and is an improvedtire 10 where the overall tire is preferably of the pneumatic versionand configured in the standard toroidal shape with an opening in themiddle for receiving a wheel rim. The improved tire 10 as shown in crosssection in FIG. 1, involves a tire construction that is extremely stiffin the in-plane torsional direction but flexible in the radialdirection.

Specifically, tire 10 includes a wall 11 configured in a C-shaped mannerand extending circumferentially around an imaginary central axis therebydefining the center rim opening 12 and an air holding cavity 13 of thestandard toroidal shape. Specifically, wall 11 has two sidewall regions14 and 15 separated by a tread region 16 including land areas andgrooves therebetween in any of the many tread patterns well known in theart. The sidewall regions 14 and 15 each extend from a bead area 17 tothe tread region 16. The sidewalls are generally curved, while the treadregion is generally planar or only slightly curved.

The construction of C-shaped wall 11 of tire 10 is constructed of atleast one carcass ply 21, and in accordance with the invention a singlebelt structure consisting of at least one continuous annular beltindicated generally at 20. Belt 20 is formed by a plurality of hingedlylinked rigid plates 22 encapsulated in a rubber compound 23. The wall 11also includes a steel wire bundle 24 in the bead area 17 to hold tire 10to a rim when properly mounted thereon. The carcass ply wraps aroundbead wire 24.

The carcass ply 21 is of a standard construction encompassing one ormore plies, each of which includes a plurality of elongated strands ofsteel or other internal reinforcing metal or synthetic cords. The pliesare configured in relation to each other as is well known in the artsuch as in a bias or radial manner. Fabric or other material maysimilarly be positioned in between the ply layers as is well known inthe art.

Each plate 22 of link belt 20 is a narrow and relatively planar piece ofsteel or other metal, or alternatively any other similarly stiff andextremely hard material. The relatively planar plates are designed andplaced to rigidly follow the contour of the outer radius of the tire andtherefor are either flat or slightly curved depending upon the contourof the outer radius of the tire design.

Alternatively, the plates 22 may be manufactured out of a lightcomposite material having sufficient stiffness to meet the in-planetorsional demands of the present invention. The plates may also beconstructed in a honeycomb manner rather than in a flat, solid nature.In the honeycomb embodiment, the tread rubber 23 fills the cells duringthe molding process which further enhances stiffness while keepingweight down.

The plates 22 each have a pair of opposed end edges 25, a pair ofopposed side edges 26, and a pair of opposed faces 27. The faces aresandwiched in rubber compound between the tread region 16 and carcassply 21 as is shown in FIG. 2. The side edges of adjacent plates areabutted and hinged together as described below around the entire outerradius of the belt as is shown in FIG. 1.

Specifically, each of the plates 22 is connected to the plates adjacentthereto along the side edges of the respective plates by hinges 30. Thehinges 30 may take various forms as described below, including rubbermolded between the plates or mechanical links. The plates 22 wheninterconnected form a stiff annular ring supported by the sidewalls 14and 15.

After the belt has been assembled in layers if multiple plies are used,and after the plates have been positioned long the outer radius of thebelt and fastened together using hinges 30, the rubber compound 23envelopes or encapsulates the entire belt, the wires, and all of theplates within a mold and is vulcanized resulting in a finished tire, asis shown in cross section in FIG. 2, with some tread configurationincluding land areas and grooves as needed to meet various environmentaland performance criteria.

The hinge 30 connects adjacent plates in a manner so as to allow bendingat the hinge connection such that the plates curve around the outerradius of the belt where the tread region will be defined after therubber compound is molded. These plates 22 are thus a flexible ring ofrigid plates connected by flexible hinges 30. The tire is flexible whenfaced with a radial force F1 (FIG. 2) because each plate 22 is moveableradially inward and outward in relation to the adjacent plates due tothe flexibility of the hinge 30. However, the plates 22 are rigidlyconnected and relatively immovable when faced with a torsional force T1,particularly an in-plane or steering torsional force, because the plateswill not displace or move planarly in relation to the adjacent plates.

In operation, when the in-plane or steering torsional displacing forceT1 is applied, the side edges of the plates as flexibly connected by thehinge 30, come into solid contact with each other and create a nearlyrigid structure while the belt remains flexible in the radial direction.By maintaining flexibility in the radial direction even during torsionalloading, the tire demonstrates good cornering properties whilemaintaining a soft ride. The term "steering torsion" means rotationabout the axis in the equatorial plane of the tire, wherein the"equatorial plane" is the plane perpendicular to the axis of rotationthrough the center of the tire.

Five different hinge embodiments are shown in FIGS. 3-7A. The firsthinge embodiment is shown in FIGS. 3 and 3A and has a flexibleconnection such as a bead of flexible compound, particularly rubber bead40 placed between adjacent plates 22. The rubber bead, depending uponthe type of rubber used, either adheres to the substantially abuttingadjacent plates thereby connecting the plates together, or is in a gapseparating adjacent plates and adheres to the adjacent plates therebyconnecting the plates together, or merely supplies flexible rubber in agap between the plates as part of the rubber compound 23 that envelopesthe plates 22 and carcass 21. In either case, the rubber hinge 40positioned in between the plates defines a flexible connection inbetween adjacent plates and supplies, in conjunction with the rigidplates, flexibility in the radial direction even during torsionalloading, while maintaining sufficient stiffness in torsional loading.The result is a tire that demonstrates good cornering properties whileproviding a soft ride.

The second hinge embodiment is shown in FIGS. 4 and 4A and includes oneor more mechanical links 50 connecting adjacent plates. Preferably, theplates 22 have rounded side edges as is shown in FIGS. 4 and 4A. Thelinks 50 hold the plates together while allowing the plates to pivot inrelation to each other along the abutting rounded edges 51.Specifically, the links are typically made of a flexible or elastic typematerial that allows pivoting while permitting the plates to reboundback. The links 50 function to tie or otherwise pivotably attach theplates together. The link is any mechanical structure capable ofpivotably attaching the adjacent plates such as a clip, tie, staple,strap, fastener, looped wire, or any other connector.

In the embodiment shown in FIGS. 4 and 4A, the link is a number offlexible square shaped clips or links 50. Each clip 50 has two plateengaging legs 52 and two connecting legs 53. The plate engaging legs 52are threaded or otherwise extend through holes formed in the plates in asecure yet flexible manner. The connecting legs 53 extend between theplate engaging legs 52 to provide the necessary coupling of the plates.The link is made of a material of sufficient flexibility so as to allowbending and flexing of the legs 53 as needed in order to supply, inconjunction with the rigid plates, flexibility in the radial directioneven during torsional loading while maintaining sufficient stiffness intorsional loading.

The third hinge embodiment is shown in FIGS. 5 and 5A as a mechanicalswinging hinge 60. Hinge 60 includes connector plates or flanges 61integrally connected to rotatable tube 62. At least one connector plate61 is associated with each of the adjacent plates at each hingeconnection. An elongated pivot bar or cylinder 63 is inserted axiallyinto the aligned rotatable tubes 62 of each of the hinges 60. The flatflange 61 extends outward from the tube 62 and is securely affixedwithin or on the plate 22 as is shown in FIGS. 5 and 5A. This securingmay occur by welding, fastening (such as by rivet or screw), or thehinge may have been bonded or molded within the plate at the formationof the plate. The embodiment shown in FIGS. 5 and 5A, has the hinges 60inserted within slots cut in the sides 26 of the plates whereby thesteel or other material from which the plate was made has integrallyflowed into holes 64 thereby securing the hinge within the plate.

The fourth hinge embodiment is shown in FIGS. 6 and 6A and is a tongueand groove hinge 70. Hinge 70 includes a tongue 71 extending outwardfrom the side edge of one of the plates 22 and a groove 72 cut withinthe side edge of the adjacent plate 22. The tongue 71 is swivelablyseated within the groove 72. The tongue 71 is generally longer than thegroove 72 is deep thereby allowing for some pivoting of the adjacentplates based upon the tongue moving within the groove. The shape of thetongue and groove may vary. However, the shapes includes an elongatedcylindrical tongue transversely connected to the side edge and capableof a snap-fit or sliding engagement into an elongated cylindrical slotgroove as shown in FIGS. 6 and 6A, as well as one or more ball andsocket arrangements where one or more round tongues are insertable intoone or more corresponding round holes, or an elongated locking ridgeslidably inserted within an elongated groove.

The fifth hinge embodiment is shown in FIGS. 7 and 7A as aconvex-concave hinge 80 wired or otherwise held together. The hinge 80includes a convex face 81 cut in the side edge of one plate 22 and aconcave face 82 cut in the side edge of an adjacent plate 22. The convexface 81 pivotably seats within the concave face 82 thereby allowingradial motion. One or more wires 83 are threaded through or integrallyformed in plates 22 in a wave-like manner as shown in FIGS. 7 and 7A tosupply sufficient tautness to the concave-convex sockets to hold themtogether while still allowing the needed pivotal movement during theapplication of radial forces to the tire.

In any of these or other embodiments, the plates 22 may have roundedside edges as is shown in FIGS. 4 and 4A to allow for more easydeformation in a radial inward manner when a radial force is applied tothe tire. This will enable the tire to absorb larger bumps better, aswell as diminishing the force transmitted to the spindle in comparisonto conventional tires.

The width of plates 22 is not critical. The plates of a given tire mayall be of the exact same width dimension from side edge to side edge.Alternatively, the widths may vary from plate to plate which functionsto minimize or treat noise by minimizing cyclical noise.

This new tire design also provides a unique tire foot print. The footprint will be substantially flat and rectangular due to the rigidity ofthe plates 22.

In high speed and high temperature conditions, conventional radial tirestend to bulge in the middle of the tread. The plates due to its extremestiffness act to minimize or eliminate this bulging problem.

Another problem often present in standard radial tires is ply-steer. Thesymmetrical design of the belt in the present invention acts to minimizeor eliminate this ply-steer.

The present invention is applicable to all radial tires that have beltsdesigned therein, and is especially applicable to passenger tires, racetires, light truck tires, truck and bus tires, and temporary sparetires.

Accordingly, the improved multiple link tire belt is simplified,provides an effective, safe, inexpensive, and efficient tire whichachieves all the enumerated objectives, provides for eliminatingdifficulties encountered with prior tires, and solves problems andobtains new results in the art.

In the foregoing description, certain terms have been used for brevity,clearness and understanding; but no unnecessary limitations are to beimplied therefrom beyond the requirement of the prior art, because suchterms are used for descriptive purposes and are intended to be broadlyconstrued.

Moreover, the description and illustration of the invention is by way ofexample, and the scope of the invention is not limited to the exactdetails shown or described.

Having now described the features, discoveries, and principles of theinvention, the manner in which the improved pneumatic tire containing amultiple link tire belt is constructed and used, the characteristic ofthe construction, and the advantageous, new and useful results obtained;the new and useful structures, devices, elements, arrangements, parts,and combinations are set forth in the appended claims.

I claim:
 1. A pneumatic tire that is extremely stiff in the in-planetorsional direction but flexible in the radial direction, said tirecomprising:an annular carcass having at least one ply, the plycomprising a plurality of elongated strands; a single belt structureconsisting of at least one flexible annular belt each comprised of aplurality of rigid plates, each plate separated from and pivotallyconnected to an adjacent plate by a pivot means comprising a tongueextending from one plate swivelably seated within a corresponding grooveformed within an adjacent plate; and a rubber compound enveloping thecarcass and at least one flexible belt.
 2. The pneumatic tire of claim 1wherein the tongue is an elongated cylinder transversely connected tothe one plate and the groove is an elongated cylindrical slot cut in theadjacent plate.
 3. The pneumatic tire of claim 1 wherein the tongue is aball and the groove is a socket.
 4. A pneumatic tire that is extremelystiff in the in-plane torsional direction but flexible in the radialdirection, said tire comprising:an annular carcass having at least oneply, the ply comprising a plurality of elongated strands; a flexibleannular belt comprised of a plurality of rigid plates, each plateseparated from and pivotally connected to an adjacent plate by a pivotmeans comprising a tongue extending from one plate swivelably seatedwithin a corresponding groove formed within an adjacent plate, whereinsaid tongue is a ball and the groove is a socket; and a rubber compoundenveloping the carcass and flexible belt.